Rib Eye Area and Grading. REA ranged from 7.3
in2 to 15.9 in2, with an average of 10.2 in2 and standard
deviation of 1.9 in2 (Figure 5a). Standard deviation
is a measure of variability among individual values.
Marbling score ranged from 310 (slight = low Select grade) to 740 (slightly abundant =mid-Prime grade),
with an average of 450 (small = low Choice grade) and
standard deviation of 85 (Figure 5b).